There was a boardwalk in St. Joseph. It was called Silver Beach Amusement park and paradoxically enough was located where the Silver Beach County park is located today.
It operated from 1891 to 1971 and was torn down in '73 or '74.
But it ended up like this:
source:
http://rememberingsilverbeach.com/index.html
I don't have any real sources to back up my hypothesis but I imagine most tourist towns on Lake Michigan followed a similar path. The late 19th and 20th centuries were boom times for tourism and coincided with fruit shipment to Chicago. St. Joseph and Benton Harbor had mineral baths and health spas where Chicagoans would go for vacation. Hotels were built in both St. Joseph and Benton Harbor like the Whitcomb Hotel.
However, when Lake Michigan fruit shipping began to decline along with other Lake Michigan shipping, tourism was replaced with manufacturing in many of the larger coast cities. SJ/BH had a huge number of large manufacturers, number one of course being Whirlpool. Manufacturing was profitable and the two cities reached their peaks. Pollution and invasive species diminished what was left of the tourist industry through the 50s, 60s, and 70s. The 1970s being the nadir for Lake Michigan health. In fact when I was born, living on the beach was looked down upon.
We all know what happened to manufacturing in Michigan during the 80s and 90s and unfortunately, Benton Harbor bore the brunt of it. BH was a pretty sizeable city at one point in time. Next time you're in town drive around downtown and imagine all the empty lots and parking filled in.
The lake became cleaner, thanks in part to the zebra mussels, and there were less ale wives, so people from Chicago began coming over and discovering Southwest Michigan once again. Benton Harbor looks better than it has my entire life, not that that is saying much and it certainly hasn't helped the vast majority of its residents, but there are actually businesses downtown.